Device for intaglio printing



Juhe 5, 1928. 1,672,073

W. E. MOLINS DEVICE FOR INTAGLIO PRINTING Filed Oct. 1926 lnveniorPatented June 5, 1928.

UNITED STATES.

. WALTER EVERETT MOLINS, F DEPTFORD, LONDON, ENGLAND.

DEVICE FOR INTAGLIO PRINTING.

Application filed October 7, 1926, Serial No. 140,161, and in GreatBritain October 17, ,1925.

This invention is for improvements in or relating to a device forintaglio printing, and more particularly to a process of. or a devicefor imprinting by intaglio, multicoloured impressions upon atravellingweb of material.

It is found in practice, where a coloured design is periodically.reproduced upon a travelling web of material by a series of engravedrollers each adapted to apply a different coloured impression to theweb, that the coloured design imprinted upon the web by any one roller,is not sufficiently dry before it reaches the next succeeding roller toprevent a certain amount of ink from the impression being deposited uponthe surface of the next printing roller, and being thereafter carriedinto the ink bath of that roller, causing the ink to become graduallycontaminated with the colour of the preceding unit.

Further, as the amount of set off ink which is deposited by oneimpression upon the surface of a printing roller is very small, itsimmediate effect upon the ink of the succeeding printing unit is notnoticeable and it is only the accumulative effect of the set off ink ofseveral impressions which produces any visible alteration in the qualityof the ink of a printing unit. Due to this fact considerable difiiculty'has been experienced in finding effective means for dealing with thesesmall quantities of set off ink. Thus if an additional doctor blade isem ployed upon each printing roller for the express purpose of removingany set off ink which may be deposited upon the surface thereof, it isfound that the set off ink is liable to cake upon the edge of the bladeand so scratch the surface of the roller besides eventually renderingthe doctor blade ineffective.

It is an object of the present invention to provide means which willensure that the set off ink of one impression is removed from the webprior to the next succeeding coloured impression being applied thereto.

Further the present invention consists of an intaglio printing machinefor use in printing multi-coloured impressions upon a travelling web ofmaterial, whereln means disposed between two successive printing unitsare arranged to remove from the web any set off ink of one impressionprior to the web receiving the next successive coloured impression. I

The invention is hereinafter more particularly described with referenceto the accompanying drawing, which illustrates a portion of an intaglioprinting machine.

Referring to the drawing, an engraved roller 1, carried in bearingssupported by the frame of a printing machine, is adapted to receive inkfrom a transfer roller 2 arranged to rotate in an ink duct 3 byfrictional contact with the roller 1. The transfer roller 2 is carriedupon a bell crank lever 1, one limb of which is adapted to engage with aspring 5 which presses the roller 2 into engagement with the surface ofthe engraved roller 1. j

A doctor blade 6, adapted to engage with the surface of theengraved-roller 1, is carried upon a spindle 7 which is arranged to bereciprocated in the direction of the longi tudinal axis pf the roller 1.

Adapted to bear upon the engraved roller 1 are a pair ofpressure rollers8, preferably constructed according to specification No. 243,909.Mounted between the engraved roller 1 of one printing unit and theengraved roller of a second printing unit is a set off roller 9 adaptedto engage with a transfer roller 10 which is arranged to rotate in theink duct 3 in a manner similar to the transfer roller 2. A doctor blade11, which may, if necessary, be reciprocated in the direction of theaxis of the roller 9 is arranged to engage with the surface of the setoff roller 9 so as to remove any ink from the surface thereof. A pair ofpressure rollers 12, preferably constructed according to specificationNo. 243,909, are carried upon a bracket 13 pivoted upon 3a pin 14 so asto be easily swung out of engagement with the roller 9 into a ositionabove the pressure rollers 8. The'pressure rollers 12 are held inengagement with the set off roller 9, by means of an arm 15 adapted tobe snapped into engagement with a cam surface 16, formed on the endofthebracket 13.

A travelling web, 17 of paper is adapted to be fed between a series ofengraved rollers 1 and the pressure rollers 8 to receive a series ofcoloured impressions. After the web 17 leaves the roller 1 of eachcolour impression it passes between the set off roller 9 and thepressure rollers 12.

The operation of the machine is as follows :-'The web 17 receives acoloured im- 1 that impression which may exist upon the surface of theweb is transferred to the surface of the set off roller 9. The roller 9receives a coating of ink from the transfer roller 10, which mixes withthe set off ink on the surface of the roller 9 and maintains the same ina liquid condition.

The ink spread upon the surface of the set off roller 9, is removed bythe doctor blade 11 and transferred to the ink duct 3 which provides inkto both the engraved roller 1 and the set H roller 9.

Thus it will be seen that the set off ink which is transferred from theweb to the set ofi' roller 9 is conveyed back into the ink duct fromwhence it came, and the web 17 passes on to receive a further colouredimpression, free front any set off ink which might otherwise contaminatethe ink of a second printing unit.

It will be appreciated that the web may be embossed upon the samemachine upon which it is printed, in which case a set ofi roller orrollers would be disposed between the printing roller and the embossingroller in order to prevent any contamination of the surface of theembossing roller.

What I claim as my invention and desire to secure by Letters Patentis 1. An intaglio printing machine for use in printing multi-colorimpressions upon a travelling web of material which comprises incombination at least one set-ofi' roller disposed between two successiveprinting units and arranged to engage with the printed surface of theweb prior to the same engaging with the next successive printing unit,means for applying a liquid deposit upon the surface of the set-offroller after the same has engaged with the printed surface of the web,and means for removing said liquid deposit from the surface of theset-oil roller, prior to the salne engaging with the surface of the web.

2. An intaglio printing machine for use in printing multi-colorimpressions upon a travelling web of material wherein at least oneset-oif roller is disposed between two successive printing units andarranged to engage with the printed surface of the web prior'to the sameengaging with next successiveprinting unit, a transfer roller mounted inthe ink duct of the first printing unit and arranged to apply a depositof ink upon the surface of the set-off roller after the same has engagedwith the printing surface of the web and means for removing said depositof ink from the surface of the set-off roller and depositing the same inthe ink duct of WALTER EVERETT MOLINS.

